Sen. Ted Cruz (R) of Texas speaks during the family leadership summit in Ames, Iowa, on Aug. 10. Senator Cruz said in a statement on Aug. 19 that he will renounce his Canadian citizenship, following a report by The Dallas Morning News that he holds dual US and Canadian citizenship.

The freshman Republican senator from Texas – and possible 2016 presidential candidate – announced Monday evening he is renouncing the Canadian citizenship that, until just a few days ago, he didn’t think he had.

Yes, Senator Cruz was born in Canada, and thus automatically a Canadian citizen. But he was born to an American mother – the former Eleanor Wilson, born in Wilmington, Del. – and that makes Cruz a “natural born” citizen in the eyes of most legal experts. That phrase – natural-born citizen – appears in the Constitution as one of the eligibility requirements for the US presidency.

Having acknowledged in a statement Monday that he “may technically have dual citizenship,” following a report in The Dallas Morning News, Cruz took the expected next step: to say that he will give up the Canadian part.

“Nothing against Canada, but I’m an American by birth and as a US senator, I believe I should be only an American,” Cruz said.

As a political matter, that belief would logically be extra-strong for anyone thinking of running for president. After all, Americans want their presidents to bleed red, white, and blue, not maple syrup.

But would holding dual American-Canadian citizenship have prevented Cruz from legally running for president? There’s no clear answer, since the Constitution is silent on that question, and the courts have not addressed it.

Chances are, anyone in Cruz’s situation – that is, born outside the US to at least one American citizen in a country, like Canada, that automatically confers birthright citizenship – would do what he did: Give up the non-American citizenship for political reasons. That takes care of the legal question before it reaches a courtroom.

But if Cruz does run for president, and he’s showing all the telltale signs – such as traveling to Iowa and New Hampshire – then chances are, questions about his eligibility will continue to pop up. Actually, one could say that he faces a harder argument against his eligibility than Mr. Obama did. Obama was born in the United States and released the long-form version of his Hawaiian birth certificate in 2011 to prove it (though to birthers, that proved nothing). He was also born to an American mother.

In fact, Obama could have been born in Kenya to his American mother, and still have been eligible to be president. Or he could have been born to two non-US citizens on American soil and still been eligible.

Cruz, too, has released his birth certificate, showing that he was born in Calgary, Alberta, on Dec. 22, 1970, to an American mother and a Cuban father. The Cruzes were living in Calgary, because they had started a seismic-data business there. When Ted was four, they moved to Texas and stayed there. Cruz’s father, Rafael Cruz, became a naturalized American citizen in 2005.

So, as long as Cruz behaves like a presidential candidate, will he face questions from birthers? There’s some irony to that question. The birthers who have consistently questioned Obama’s eligibility for the presidency, no matter how much evidence he produces, are typically conservatives, many of them tea party supporters.

Cruz was elected to the Senate last November on a wave of tea party support. Now, the shoe’s on the other foot; some liberal bloggers have suggested that Cruz’s Canadian birth disqualifies him for the presidency.

The problem is that Article II, Section I of the Constitution does not define the phrase “natural-born citizen,” and so its meaning has come to be understood via a consensus of legal scholars over the generations.

A 2009 study by the nonpartisan Congressional Research Service (CRS) defines “natural born” US citizenship as being conferred either “at birth” or “by birth” – and includes, as an example, the circumstance of Cruz’s birth.

“The weight of scholarly and historical opinion appears to support the notion that ‘natural born citizen’ means one who is entitled under the Constitution or laws of the United States to US citizenship ‘at birth’ or ‘by birth,’ including … those born abroad of one citizen parent who has met US residency requirements,” wrote Jack Maskell, a CRS legislative attorney.